Superpedestrian announced today that has raised a $16.5 million round to continue developing its technologies for electric bike-sharing companies.

Based near Boston, the transportation robotics company is known for creating the Copenhagen Wheel, which contains a small motor that is rechargeable, essentially turning a bike into a hybrid electric vehicle.

The wheels contain sensors, embedded controllers, and software that help ease management of bike-sharing fleets. The company sells the wheels, a complete bike, and a bike-sharing system and platform.

The latest round of funding includes money from Extol Capital’s Charles Kim, Spark Capital, and General Catalyst. It also includes money from Nest cofounder Tony Fadell. Superpedestrian has now raised a total of $44 million.

“Superpedestrian’s technology overcomes the major issues faced by this growing industry,” said CEO Assaf Biderman, in a statement. “Our e-bikes autonomously manage themselves through onboard diagnostics, self-protection, and self-calibration and then connect to a remote maintenance system that can service the entire fleet. If you rely mostly on users to report that something is broken, that’s too late. We know what’s going on inside each of our e-bikes and can resolve most issues before they occur.”

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